Theoretical Research On The DORIS System Based On The Spectrum Spreading Technique

In recent years, the use of the French DORIS system to achieve high-precisionorbit determination of satellite has become hot in our research in space field.Spreadspectrum technology is widely used in navigation, positioning and other fields for itsstrong anti-interference ability. Theoretical analysis and project feasibility study of theapplication of spread spectrum technology in a DORIS system are mentioned in thispaper.Firstly, a detailed introduction of the DORIS system is made, including itscomposition, working principle and its advantages and disadvantages. According to thecharacteristics of the DORIS system beacon station transmitting signal, we adopt thedirect sequence spread spectrum technology to achieve the spread of the spectrum of theDORIS beacon signal, which aims to expand the system uplink bandwidth and enhancethe anti-jamming capability, thereby improving system performance. By employingUQPSK modulation system, we achieve the complete transmission of the navigationdata and save the transmission bandwidth. Then the capture of the PN code is arrived atby the use of the parallel matched filter. PN code and carrier tracking are reachedthrough pseudo code delay locked loop and carrier Coast ring. At last, a simulation withMATLAB’s Simulink toolbox for the transmitter part of the spread spectrum in theDORIS system is done, verifying the correctness of theoretical analysis and feasibility.